In a so-called mirror-less SLR digital camera, an image of a subject can be confirmed through a so-called live view operation in which an image according to an image signal obtained by imaging in an image sensor such as a charge coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS) image sensor is displayed in real time on a liquid crystal panel provided on a back surface of a housing or an electronic view finder (hereinafter, an EVF) attached to an upper portion of the housing.
However, in this live view, a long delay occurs from imaging of a subject in the image sensor to displaying on the view finder. Therefore, it becomes difficult to cause a camera to follow a moving subject. Further, when imaging of a still image is instructed based on the displayed image of a subject, a difference in a timing is generated between the displayed image of the subject and the image of a still image that is actually captured. In particular, it becomes difficult to capture an intended still image in the case of a fast moving subject.
Therefore, a technology for shortening a delay from capture in an image sensor of an image signal displayed on the view finder or the like has been known (for example, PTL 1).